Untitled

if exists insert else update
insert into systemdetail
    (systemname, projectname, systemtype)
    select  distinct T.systemname, T.projectname, S.model
        from    sysList T, requestSystems S
        where   T.systemname = S.systemname and
            S.systemname not in
            (
            select d.systemname, d.ProjectName from systemdetail d,syslist t2 where t2.systemname = d.SystemName and t2.projectname=d.ProjectName
            )

if (exists (select sd.projectname, sd.systemname from systemdetail sd, sysList t where t.projectname = sd.projectname and t.systemname = sd.systemname)
    update systemDetail
    set projectname = t.projectname,
    systemname = t.systemname
    where ??? <-- this is where I'm stuck
else
    insert into systemdetail
    (systemname, projectname, systemtype)
    select  distinct T.systemname, T.projectname, S.model
        from    sysList T, requestSystems S
        where   T.systemname = S.systemname and
            S.systemname not in
            (
            select d.systemname, d.ProjectName from systemdetail d,syslist t2 where t2.systemname = d.SystemName and t2.projectname=d.ProjectName
            )

-- Try update first
UPDATE
    S
SET
    systemtype = X.model
FROM
    systemDetail AS S
JOIN
(
    SELECT DISTINCT
        T.systemname, T.projectname, S.model
    FROM
        sysList T, requestSystems S
    WHERE
        T.systemname = S.systemname
) AS X
ON
    X.systemname = S.systemname
AND X.projectname = S.projectname

IF @@ROWCOUNT = 0
BEGIN
    insert into systemdetail
    (systemname, projectname, systemtype)
    select  distinct T.systemname, T.projectname, S.model
        from    sysList T, requestSystems S
        where   T.systemname = S.systemname and
            S.systemname not in
            (
            select d.systemname, d.ProjectName from systemdetail d,syslist t2 where t2.systemname = d.SystemName and t2.projectname=d.ProjectName
            )
END